Superconducting Quantum Interference Devices (SQUIDs) can comprise tiny loops of superconducting material in which Josephson Junctions are placed in the loop path. A Josephson Junction can be a region of material that provides a weak link between two fully super-conducting regions. Superconducting electrons can quantum mechanically tunnel across the Josephson Junction in a well-understood process.
The DC SQUID can have two symmetrical Josephson Junctions, and DC SQUIDs can typically sense extremely small magnetic fields. Non-uniforms arrays of DC SQUIDs and DC bi-SQUIDs, which are DC SQUIDs with an additional Josephson Junction bisecting the superconducting loop, have been modeled in different array designs and coupling schemes in the prior art, to determine their linearity and sensing capacities and have been fabricated in low temperature superconducting materials. A SQUID-based sensor can detect minute magnetic fields and can be decoupled from the size of the signal wavelength. As a result, the sensors can sense signals over a wide range of frequencies, from the direct current (DC) to the Gigahertz (GHz) range, but still be contained fully on a 1×1 cm chip.
SQUID arrays are now being explored for RF detection purposes. SQUID and bi-SQUID arrays that are designed for radio frequency (RF) detection throughout the high frequency (HF) to Ultra-High Frequency (UHF) range have been fabricated in low temperature superconductor (LTS) region of operation using Niobium (Nb) substrate material. For a field deployable system, high temperature superconductor (HTS) arrays are being explored due to the reduced size, weight and power (SWaP) of the cryopackaging. The resulting reduced-SWaP systems can more easily fit on a small platform. Some HTS SQUID arrays with non-uniform loop sizes have been fabricated and have demonstrated a desirable, similar single anti-peak feature as that present in the LTS SQUID arrays with non-uniform areas. But in order to increase the signal detection performance, a high temperature super-conductor (HTS) Bi-SQUID by utilizing step-edge junctions can now be desired.
In view of the above, it can be an object of the present invention to provide a step edge bi-SQUID and method for manufacture that allows for HTS operation. Another object of the present invention can be to provide a step edge HTS bi-SQUID (Hi-SQUID) that can require a reduced SWaP, when compared to Low Temperature Superconducting (LTS) variants. Yet another object of the present invention can be to provide a step edge Hi-SQUID and method for manufacture that incorporates step edge bi-SQUIDS without sacrificing linearity of anti-peak response. Another object of the present invention to provide a step edge Hi-SQUID and method for manufacture that can be consistently fabricated in a cost-effective manner.